Active agents, e.g., pharmaceuticals, nutraceuticals, and the like, intended for oral administration are often provided in solid form as tablets, capsules, pills, lozenges, or granules. Oral dosage forms are swallowed whole, chewed in the mouth, disintegrated in the mouth and swallowed, or dissolved sublingually.
When administered orally, simethicone is used as an adjunct in the symptomatic treatment of flatulence, functional gastric bloating, and postoperative gas pains. The clinical use of simethicone is based on its antifoam properties. Silicone antifoams spread on the surface of aqueous liquids, forming a film of low surface tension and thus causing the collapse of foam bubbles. Thus, for self medication in over-the-counter preparations, simethicone is used as an antiflatulent to relieve symptoms commonly referred to as gas, including upper GI bloating, pressure, fullness, or stuffed feeling. It is often combined with other gastrointestinal medications, such as antacids, antispasmodics or digestive enzymes and various simethicone formulations are previously disclosed.
Simethicone can be administered orally as a liquid preparation or as solid form for example capsules, chewable or swallowable tablets. The advantage of tablets over liquids is the ease of portability. The advantages of swallowable tablets over chewable tablets include the ease of ingestion and lack of taste. Coated tablets are preferred for swallowable tablets.
Historically, in preparing solid simethicone dosage forms, difficulties have been encountered when attempting to incorporate substantial quantities of the liquid simethicone in the solid final blend for tableting. The difficulty has been to achieve sufficient flowability for processing and sufficient cohesion for compaction, particularly for direct compression tableting, so that the tablet will withstand the rigors of further processing, e.g., film coating, gelatin dipping, printing, packaging and the like. Likewise, difficulties have been encountered in assuring that the viscous liquid simethicone is uniformly distributed throughout the solid formulation and expeditiously dispersed upon administration.
Japanese Patent No. SHO 39[1961]-46451 to Kitsusho Yakuhin Kogyo KK discloses a method for preparing simethicone tablets by mixing and granulating simethicone with aluminium silicate, magnesium aluminum metasilicate, and magnesium silicate. In particular, the formulation disclosed by the above Japanese patent requires at most 25% simethicone and 75% or greater silicate, binder and dispersing agent. Binders were disclosed as being starch and lactose. Dispersing agent was disclosed as being carboxymethylcellulose. Further, the above Japanese patent discloses that when the amount of simethicone exceeds 25%, a portion of the simethicone can be carried away, therefore the tablet workability is not desirable.
JP 5097681 to Horii Yakuhin Kogyo KK discloses a preparation wherein simethicone is adsorbed to magnesium aluminate metasilicate and dextrin. Excipient was then added and the preparation was tableted. Following tableting a hydroxypropyl methylcellulose phthalate coating was added, followed by applying additional simethicone and gelatin. The amount of simethicone in the final tablet was about 15%.
U.S. Pat. No. 4,906,478 discloses a simethicone preparation including a powdered combinate of particulate calcium silicate and simethicone. U.S. Pat. No. 5,073,384 discloses simethicone preparations including combinates of water soluble agglomerated maltodextrin and simethicone. U.S. Pat. No. 5,458,886 discloses a free-flowing granular composition including titanium dioxide having specific particle size and surface area in combination with simethicone.
U.S. Pat. No. 6,103,260 describes the use of an admixture of simethicone and either one or both of granular anhydrous tribasic calcium phosphate or dibasic calcium, wherein the admixture in a uniform granular composition of not more than 1000 micron particle size, that is suitable for compression into a solid dosage form for oral administration. While the amount of simethicone in the final composition was disclosed as being 10% to 50%, the final tablet weight was in excess of 1000 mg.
What is needed, therefore, is a free-flowing compressible composition containing simethicone for forming a solid dosage, wherein either larger quantities of simethicone can be incorporated therein or smaller solid dosage forms containing the same amount of simethicone.
Surprisingly, it has been discovered that using silicified microcrystalline cellulose and magnesium aluminometasilicate as substrates onto which simethicone or other oil or liquid active is adsorbed provides such a composition. Thus, there is provided by the present invention a free-flowing compressible composition containing simethicone for forming a solid dosage form that contains either larger weight percentages of simethicone while maintaining substantially the same size than previously possible or the same weight percentage of simethicone in a smaller size. In addition, the present invention is directed to such solid oral dosage forms and related processes.